The present invention relates to electrostatic copying machines of the type provided with flash-lamp fixing units. The flash lamp of the fixing unit emits a brief intense flash of radiant energy which raises the toner of the toner image on the copying medium to melting temperature and causes the toner image to be fused.
Copying machines of this type, provided with so-called flash-lamp fixing units, are disclosed for example in German allowed patent application No. 1,063,029, German published patent application No. 1,597,898 and German published patent application No. 1,908,827. It has been found that the performance of a flash fixing operation requires the use of high-energy flashes of radiation. As a result, when a flash operation is performed, a very sizable quantity of ozone may be generated in the air surrounding the flash lamp. Also, the intensity of the flash irradiation can result in partial decomposition of the relatively complex plastics of which the toner powder may be comprised into constituent components which, particularly if they vaporize, can be dangerous to inhale. If the number of flash operations performed per unit time are increased beyond a certain limit, the amount and concentration of environmentally undesirable and health-injurious ozone and toner vapors discharged to the exterior of the machine can become very serious.